feat(subagent): include tool call arguments in ToolResult events and progress formatting

src/app/subagent/engine.rs

@@ -582,6 +582,7 @@ pub fn run_subagent(ctx: &SubagentContext, tx: &mpsc::Sender<SubagentEvent>) ->
                         messages.push(ChatMessage::tool_result(tool_call.id.clone(), output_text.clone()));
                         let _ = tx.blocking_send(SubagentEvent::ToolResult {
                             tool: tool_name.clone(),
+                            args: args.clone(),
                             output: output_text,
                         });
                     }
@@ -598,6 +599,7 @@ pub fn run_subagent(ctx: &SubagentContext, tx: &mpsc::Sender<SubagentEvent>) ->
                         messages.push(ChatMessage::tool_result(tool_call.id.clone(), msg.clone()));
                         let _ = tx.blocking_send(SubagentEvent::ToolResult {
                             tool: tool_name.clone(),
+                            args: args.clone(),
                             output: msg,
                         });
                     }

src/app/subagent/event.rs

@@ -28,6 +28,7 @@ pub enum SubagentEvent {
     },
     ToolResult {
         tool: String,
+        args: Value,
         #[allow(dead_code)]
         output: String,
     },